Hydrophosphorylation of 1,3-diphenyl-2-propen-1-one and 4-phenyl-3-buten-2-one in the coordinational sphere of carbonyl complexes of Group VIB metals

Abstract

Synthetic procedures for preparing η2 and η4 complexes of chalcone and henzalacetone with hexacarbonyl mononuclear complexes of Group VIB metals were developed and conditions for selective η2 and η4-coordination of the heterodiene ligand were established. Hydrophosphorylation of the obtained complexes proceeds in the coordination sphere of the metal by the Abramov reaction scheme and yields the corresponding η2-coordinated α-hydroxyphosphonates. As follows from quantum-chemical calculations, π-coordination with metals makes the heterodienes no longer planar, which explains their regioselective phosphorylation by the more electrophilic carbonyl group.